How Does Wave Propagation Time Relate to Cable Length and Gravity?

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The discussion focuses on deriving the wave propagation time for a vertically hanging cable under its own weight, specifically showing that t = 2√(L/g), where L is the cable length and g is the acceleration due to gravity. Participants mention the relevant equation for wave speed, v = √(F/μ), where F represents the tension in the cable. The tension is influenced by the weight of the cable, which varies along its length. The initial poster seeks guidance on how to begin solving the problem after struggling for two hours. Understanding the relationship between tension and gravity is crucial for solving this physics problem.
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Homework Statement


Show that the time it takes a wave to propagate up the cable (cable which hangs vertically under its own weight) is t = 2\sqrt{L/g}, where L is the cable length.


Homework Equations


i think... v=\sqrt{F/\mu}



The Attempt at a Solution


i've been staring at this problem for about 2 hours now. can anyone just help me how to get started on this one??
 
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pcjang said:

Homework Equations


i think... v=\sqrt{F/\mu}

Yes. And F is the tension in the cable.
 
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